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Saturday, October 10, 2009

Human Races

A discussion about human races has broken out in the comments to The Problem of Race .... Again. One of quesitions on that thread has come up many times in the past so I'm devoting a separate posting to the answer.

Hopefully, this will stimulate discussion and debate about the scientific data and evidence for genetically distinct humans populations. I want to get away from the other aspects of the debate about races since they always seem to devolve into accusations of racism and/or political correctness. (mea culpa)

anonymous asks,

i always feel in these discussions people are talking past each other, especially when they have differing definitions of words like 'race'. so to clarify matters for me, i would like Dr. Moran to give the likely number of races that currently exist, say something on the stability of such groupings,give examples (if possible) of these racial groupings along with their differing genetic markers e.g. race 1 - geographically located in region A & B, with unique (almost Unique) gene combination 1,3,4,5 occuring at frequencies A,B,C,E.

Are you serious? Please tell me this is a joke.

Are you one of those people who want to deny the existence of races just because your question can't be answered precisely in the manner you phrase it? That sounds very much like the kind of thinking I encounter when dealing with creationists.

Biology is messy. There are no nice and tidy boundaries around terms like race, species, or even higher taxonomic levels. You may not like it but you have to deal with it. If you understand evolution then it all makes sense and you know why things are so messy.

Our species is subdivided into many different genetically isolated(1) populations ranging from very small ones, such as the residents of Tristan da Cunha, to very large ones, such as Africans and Asians.

The term "race" usually refers to the largest populations within a species. In the case of humans, the group who migrated out of Africa founded a genetically isolated population that subsequently split into several different populations. The main ones are Asian, European, Australian, and American.

These are reasonable examples of races. Each of them can be subdivided into numerous examples of demes and populations. Their genetic distinctiveness is so obvious that most of us would have no difficulty identifying their members if we encounter them on the streets of a major cosmopolitan city.(2)

The African group from which the migrants split is "polyphyletic" and deciding how to divide it into races is problematic. However, it's clearly a group that's genetically distinct from the other races so it's not unreasonable to refer to the Africans as a race, as long as you keep in mind that there are subdivisions and that this group is much more genetically divers than the others.

The genetic distinctiveness of Africans is pretty obvious to me. I'm constantly surprised by those who pretend it doesn't exist. People of African ancestry certainly don't have any trouble recognizing that I'm Caucasian and that some of my other neighbors are Asian.

There are dozens of phylogenetic trees on the web showing these major splits and subdivisions. Probably the most famous is the mitochondrial tree but others show roughly the same tree. It would be hard to imagine anyone denying the existence of human races unless they completely reject that kind of analysis.

There are several commercial, for-profit, companies that are more than willing to take your money (and your DNA) and provide you with an analysis that identifies where your ancestors came from. They are able to do this because certain haplotypes evolved in certain parts of the world. The mitochondrial haplotypes are shown on the map above and the Y-chromosome haplotypes are shown on the map on the left.

Given all the publicity about tracing your genealogy by haplotyes and all the scientific papers on the genetic differences between races, it surprises me that in 2009 there are still people who question whether these genetic differences even exist.

1. "Genetically isolated" does not mean that there's no genes flow between populations. It means restricted gene flow. If gene flow was zero they the populations wouldn't be populations. They would be species.

2. This does not mean that there won't be examples where the identification is difficult and it doesn't deny the existence of interbreeding between races. If you're looking for that kind of example then you won't find it in humans or in any other species where the biological term race is commonly used.

Larry wrote There are dozens of phylogenetic trees on the web showing these major splits and subdivisions. Probably the most famous is the mitochondrial tree but others show roughly the same tree. It would be hard to imagine anyone denying the existence of human races unless they completely reject that kind of analysis.

With all due respect, Larry, this is one of the most ill-reasoned pieces of logic I've ever encountered in this debate.

The existence of a phylogeny prove races exist? Really?

So the fact that in my family tree, I am one terminal taxon and my brother is another you would conclude that me and my brother are in different racial groups.

That's just silly, and surely a man of your intelligence knows better. So while we should just chalk that up to miscommunication, can we agree that the comment deserves clarification?

And for the record, I think you are too quick to dismiss the "how many races are there, then?" line of attack. It's a real problem, because if you are going to argue that groups exist you should be able to define the boundaries between those groups.

It really is not enough to say, anecdotally, that a "typical" person could distinguish a "typical" African from a "typical" non-African on the street. That's good bar bet material, but not necessarily good science.

"And for the record, I think you are too quick to dismiss the "how many races are there, then?" line of attack. It's a real problem, because if you are going to argue that groups exist you should be able to define the boundaries between those groups."

I agree. And I agree with what Vincent said previously. There is genetic diversity in humans, but there are no races. The human genetic diversity is continuous, and every division of this diversity would be arbitrary. And again, it may be easy for Africans to classify Larry as Caucasian and his neighbours as Asians, but just take a long trip from eastern Europe east towards Kamchatka, and tell me then, at which point on your way did people become Asians?

you are too quick to dismiss the "how many races are there, then?" line of attack. It's a real problem, because if you are going to argue that groups exist you should be able to define the boundaries between those groups.

No, it is not a real problem. Every abstract concept, be it species, trees, planets or colors does not exist with perfectly defined borders. On a continuum, there are always finer scales. That in no way means the abstract concepts are not useful and that the physical phenomena they refer to do not exist. The simplest example: How many colors exist?

To be consistent with your "it's a real problem" argument, you have to conclude that colors don't exist. Following the same line of logic you will discover that planets don't exist either.

I think the trouble is that this is a very political question since the moment you say there is a scientific basis for race you open the door for people to start ranking races and thus get racism. This debate becomes almost like lying to someone about one issue so they don't end up even more wrong on another issue.

As for the actual scientific validity I can't really comment on that but from Greg Laden's arguments he seemed to claim that the trouble was that the boundaries weren't distinct enough and that there was too much internal variation.

I'm not sure if I buy his arguments but I do think there is some justification to the complaint that most of our classifications of race occur on skin colour and to a lesser extend on facial structure.

Are these variations the best indicators to use from a scientific perspective?

I'd love to see a really decent discussion of this topic, but it has a tendency (as Larry observed) to degenerate into the realm of the ad hominem (e.g. attempts to paint participants as either "racist" or "politically correct").

One problem as I see it is that we inherited the term "race" from a time that predates much of our modern knowledge. It is not only our advances in genetic science but also changes in fields like linguistics, sociology, cultural anthropology, and so on that makes a truly objective discussion difficult.

For example, while I maintain that there are no objective (and certainly no non-arbitrary) genetic boundaries and thus no "true" genetic races that doesn't mean I am blind to genetic diversity.

A sample of people born in Calabria will generally be distinguishable from a sample of people born in Veneto, for example. But the decision to sample those two regions is generally an arbitrary one, and if you took similar samples at 10km intervals between Calabria and Veneto you'd find no place to draw a line.

That doesn't make Calabria the same as Veneto, but it should alert us to the fact that our original distinction has more to do with our sampling procedure than with any true underlying genetic "groups", "clusters" or "races".

You claim : << The African group from which the migrants split is "polyphyletic" and deciding how to divide it into races is problematic. However, it's clearly a group that's genetically distinct from the other races so it's not unreasonable to refer to the Africans as a race, as long as you keep in mind that there are subdivisions and that this group is much more genetically divers than the others. The genetic distinctiveness of Africans is pretty obvious to me. I'm constantly surprised by those who pretend it doesn't exist. People of African ancestry certainly don't have any trouble recognizing that I'm Caucasian and that some of my other neighbors are Asian. >>

I will comment only point : you are here in complete confusion of any notion of population genetics, which deals very specifically about allelic frequencies within - and between - interbreeding populations. Or with the ability to.The polyphyly is a concept that has nothing (or very little, otherwise it loses its meaning) to do intra-species, among populations interbreeding, with gene flow between them, due in part to migration and trade - or to the inheritance of alleles wich are differentially distributed by various processes, including genetic drift.The polyphyly has close relationship, and is operational only with the TAXA, and implies that a strictly phylogenetic classification is erroneous in regard of common but non-homologous characters - inherited from different ancestors.

Your full page is total mess of fantasy mixed with garbage and some technical claims or points that are a fact, but that you really DO NOT understand : your understanding of the human allelic situation and interpopulation differences is here reduced to a silly understanding through evolution only, where gene flow, migration, and any process typical of diploids, is unknown in your intellectual horizon. (*)

(*) Of course, you can always complain and say that if some populations don't interbreed, the process is the same. arf arf, Yes, you can. And you also can add any other fallacy.

It appears to me that the word "race" has come to be similar to the word "kind" that creationists use.

There should be a more scientific friendly word to describe people who share similar genes; the latter concept does make sense and IS useful at times (e. g., is it a good idea to test Swedes for sickle-cells? Or..people of African descent are often not properly treated for heart attacks as they tend to have different symptoms)

Moran said : << 1. "Genetically isolated" does not mean that there's no genes flow between populations. It means restricted gene flow. If gene flow was zero they the populations wouldn't be populations. They would be speciees >>

If a reproductive barrier is not completed between two populations => if they are not infertile between them, they are not two different biological species.This accident (the barrier) may occur, and usually occurs after a certain period of time (by fifferent ways) - can even go through the situation of partial fertility - but "no genetic flow" does not mean "separate species". No.

Moran Said : << 1. "Genetically isolated" does not mean that there's no genes flow between populations. It means restricted gene flow. If gene flow was zero they the populations wouldn't be populations. They would be species. >>

No, Mr. Moran, no. << No genetic flow >> does not mean << different species >>.

If a reproductive barrier is not completed between these two populations, c-ie if they are not infertile them, they are not necessarily two different species.This accident may occur, and usually occurs after a certain period of time - can even go through situations partial fertility - but << no genetic flow >> does not mean << different species >>.

Moran: "Given all the publicity about tracing your genealogy by haplotyes and all the scientific papers on the genetic differences between races, it surprises me that in 2009 there are still people who question Whether these genetic differences even exist. >>

Mister professor, How can you blend of " research of ascending and genealogy, through different probabilistic genetic markers" with "existence of races" ?

How can you even suggest that "people denying the scientificity of the term "race" in the human situation", deny the evidence of genetic differences ?

Mr. Moran, a little experiment: Can you tell the haplotype (s) designating only the African race ?

DK said : << No, it is not a real problem. Every abstract concept, be it species, trees, planets or colors does not exist with perfectly defined borders. On a continuum, there are always finer scales. That in no way means the abstract concepts are not useful and that the physical phenomena they refer to do not exist. The simplest example: How many colors exist? To be consistent with your "it's a real problem" argument, you have to conclude that colors don't exist. >>

Excellent. Then, race is an abstract concept. A biological abstract concept, then ?

To answer you question : how many colors exist ?

Biologically, as many as you want or as many as you believe you see. They do not exist as a biological entity, but ARE a subjective creation of our cognition/brain/eyes. Colors without our perception, are nothig else but one or more frequencies of light waves, amplitude.

<< Following the same line of logic you will discover that planets don't exist either. >>

mmmh, I just discovered that following your kind of logic, Races are like colors...

To be consistent with your "it's a real problem" argument, you have to conclude that colors don't exist.

As, indeed I would conclude. In a manner of speaking consistent with my contention that "races" are a social construct rather than a natural genetic one.

"Colors" are, like races, arbitrary and perceptive classes. I may call something "red" that you call "orange" and there would be no scientific method that could settle the matter. There is certainly no natural boundary between red and orange on the EMR spectrum, just a continuously variable range of spectral "diversity".

The other examples (species and planets) fall down, at least logically because biologists and astronomers have thankfully taken control of the language relating to them in such a way that natural boundaries (inter-reproducibility and physical contiguity) correspond to the colloquial meaning.

The colloguial meaning of "race" does not have a similar genetic equivalent.

There are many gene phylogenies that agree on the basic structure of our species. They all show, for example, that native Australians cluster together in one part of the tree and that Europeans form a pretty well defined cluster in another part of the tree.

They all agree that various African populations are the earliest branching lineages in these trees.

What does that tell us? It tells us that there hasn't been much gene flow between some groups of humans that just happen to be located in particular geographical regions.

"It would be hard to imagine anyone denying the existence of human races unless they completely reject that kind of analysis."

Your incredible, astonishing lack of "imagination" is not a valid argument. Phylogeny of human populations or ancestry recognition doesn't imply the existence of human races. Those are BIG fallacies. Very disappointing post :-(

I’m beginning to wonder if Professor Moran’s detractors are acquainted with any other species of life than Homo sapiens. Many other animals show differences in form, colour, or vocalizations, and these differences are often indicative of a slightly different habitat.

We have known for a long time exactly why there is a difference in skin colour between caucasians and negroids. As our ancestors moved outward to the northern temperate forests the reduced sunlight resulted in a deficiency in Vitamin D. Those with lighter skin therefore were better able to produce this essential chemical, were healthier, more likely to survive and breed, and therefore bred the trait into their offspring. After many generations their descendants would have the European skin colour that we are familiar with today. The skin colour difference is an adaptation to a different environment. All the while there is more than sufficient similarity between Europeans and Africans that interbreeding is accomplished with zero difficulty.

In any other species of animal we call this a race or sub-species. Why are we so afraid to treat humans the same way? I agree that the term sub-species sounds rather loaded, but it doesn’t mean inferior but sub-division. And it says nothing about the overall ability or intelligence of either people. Dark skinned people are better able to survive in the hot plains of Africa or the deserts of Australia, lighter skinned people are better adapted to temperate climates. The Inuit of the Arctic also show marked differences from those further south, with shorter and stubbier extremities to reduce heat loss.

Racists have in the past used this sort of thing as evidence that Europeans are somehow ‘more evolved’ than Africans, something which we all know is grade-A crap. Others see lighter skin as some sort of advancement or progress, which again is garbage. If early Europeans had needed to return to Africa they would have been at a disadvantage physically and would have not been able to compete with dark skinned natives; there is obviously no advancement at all. Evolution is all about adaptation and change, there is no such thing as advancement.

Rather than fostering racism, it is my opinion that a proper understanding of the reasons for our differences would help eliminate it.

There are many gene phylogenies that agree on the basic structure of our species. They all show, for example, that native Australians cluster together in one part of the tree and that Europeans form a pretty well defined cluster in another part of the tree.

Of course it is true that Europeans tend to be more closely related to other Europeans than they are to, say Australian aborigines. I haven't seen anyone here argue otherwise, which leads me to think this is just our straw man rearing his head again.

Study after study have demonstrated that genetic distance tends to correlate with geographic distance: the closer two populations are physically the more similar they are genetically, which is just a converse way of stating the true part of the statement quoted above.

That goes nowhere towards demonstrating "clusters" or races, however. If these so-called clusters actually exist, then lets see some demonstration of them.

Let's see someone explore the boundary between the European race and the Asian one. Where is the geographic point that corresponds to a point between those two "clusters"? Is a Ukrainian Asian or European? How about an Iranian? An Armenian? A southern Italian? An Ashkenazi Jew? A Yemeni?

It is not enough to type 500k SNPs on people from Japan and England and tell us that you can distinguish those samples. Of course if you sample like that your PCA plots are going to show "clusters". The trouble will come when you sample at reasonable intervals (5km, 10km, 25km, whatever). You'll find that each sample overlaps its neighbors, from Atlantic to Pacific, and you'll never find a gap wide enough to falsify the null hypothesis that humans are all one species, genetically speaking.

Not a homogenous species, mind you, but one lacking clear and natural genetic divisions. It may remain convenient to continue to use our perceptual and cultural categorizations, but let's not be lazy when it comes to our hard science.

I’m beginning to wonder if Professor Moran’s detractors are acquainted with any other species of life than Homo sapiens. Many other animals show differences in form, colour, or vocalizations, and these differences are often indicative of a slightly different habitat.

I won't speak for anyone else, and I'll admit to paying much more attention to human biology than to other species, but my sense is that systematists of all stripes are struggling with these kinds of issues.

It does take on an added dimension in human biology, for understandable reasons. But taxonomists are forever arranging and rearranging species and sub-species in ways that would surely confuse earlier generations who put sub-species in their "obvious" place.

"Their genetic distinctiveness is so obvious that most of us would have no difficulty identifying their members if we encounter them on the streets of a major cosmopolitan city."

It is for this reason that talk of 'human races' should be left to folk biology.

'Most of us' will not take phenotypic traits as a sign that human populations are the results of different historical trajectories: 'most of us' will take phenotypic differences as a proxy for other (possibly nonexistent) genetic differences; 'most of us' will take these presumed differences as predictors for other phenotypic traits shared by all members of the group/race.

Folk biology is not totally wrong, it may have some good insights in matters of classification, and mostly fails at the inferential level. Folk expectations about human races, however, are not built on human cognitive abilities alone but on human politics, and this makes reversing the folk biological view of human races even more complicate.

I think that a biologist has the right to talk about human races without being called a racist, and that the current 'biological egalitarianism' is going to backfire. But why take on yourself the additional burden of defending 'human races', where 'genetic differences at the group level' may do a much better job?

A further problem with the term 'human races' is that it provides a fertile ground for adaptationism: members of human race X will have (unsurprisingly) a certain genetic makeup wherever they happen to live; and since the prevalence of a certain genotype in a population is the outcome of differential function or performance, members of human race X will exhibit the same differences in function of performance wherever they happen to live. To be sure, the same could also be said for 'genetic differences at the group level', but the latter does not allow one easily to get away with the task of identifying the group and the distributions s/he is talking about.

So there once was a comment I made here that I saw being posted but that now suddenly disappeared without a trace. Larry, did you delete it???

If you did, your censorship it's pathetic. The worst it contained was a word "stupid". And it was a pretty well qualified epithet, BTW. Sheesh, considering the frequency you yourself use it, that's just ... you know, stupid. Stupid and absolutely cowardly.

The colour analogy is quite right, I think. There is a spectrum of different colours, true, but it is impossible to define boundaries between them. Yes, everybody agrees what is red and blue, but only to a point - I often call something blue when other people call it green.It is easy to 'define' races in a mixed population like this of US (analogous to sampling two colours from the middle of what most people call blue and green, for example), but since in reality the spectrum of human genotypes is continuous, there is no defined boundary between them (as there is no boundary between blue and green).

It is much more useful in my opinion to talk about populations. Population of people with persistent expression of lactase, population with high tolerance to some drug, population with this or that allele of MR1C, etc.

To be sure, the same could also be said for 'genetic differences at the group level', but the latter does not allow one easily to get away with the task of identifying the group and the distributions s/he is talking about.

I agree, I think. If we insist that when people talk about "populations" there is an implicit insistence that the population be defined.

For example, some recent papers on genetic diversity have defined the population of a village as that set of people who have at least three grandparents born in that village.

There may still be an arbitrary component to the definition, but at least it disabuses us of the lazy notion that the definition should be "obvious".

I'll admit that one problem I have with the concept of "race" is that it is just lazy: it demonstrates an unrigorous approach to a problem that can be approached rigorously. And intellectual rigor is one of the traits that (in my opinon) should separate scientists from IDiots.

So there once was a comment I made here that I saw being posted but that now suddenly disappeared without a trace. Larry, did you delete it???

If you did, your censorship it's pathetic. The worst it contained was a word "stupid". And it was a pretty well qualified epithet, BTW. Sheesh, considering the frequency you yourself use it, that's just ... you know, stupid. Stupid and absolutely cowardly.

If you really did censor it, I am quite shocked.

I've only ever censored two kinds of comments.

Spam gets deleted quite regularly.

A few (3?) highly offensive postings have been deleted over the three year history of this blog. I don't think your comment was one of them. The last time was months ago.

Pleas accept my apologies! I am very sorry for over-reacting. I don't know what happened then. I know I posted it as I re-read it to see how many typos were made. Oh, well. Never mind. From now on, even if it happens again, it's good to know it's not you deleting. Sorry again.

This is the anonymous that was actually quoted in the post. My intentions were not to deny the "existence of races just because your question can't be answered precisely in the manner you phrase it?" they were to explore whether the popular cultural definitions of race based on physical features such as skin colour,hair,nose, eyes have any biological basis especially when we are constantly told there is more variation within the races than between.but i want to do this in a concrete way with actual examples rather than abstract groupings that would flesh out the interplay of definitions.

i also wanted to explore the various definitions of races that people have and the evidence that support them much like what is happenning now. i am enjoying the discussions so far.

i would also like to explore the stability of races over evolutionary time and the impacts of travel and 'race mixing' on the various races.

i thought the best way to get those discussion going was through some real world examples of races and how they are determined (notice the if possible in the question? expounding further it means that you may have good solid reasons for you definition even if you don't have type specimen)

To those who are arguing that there are no races because there are no distinct boundaries: That problem exists in the classification of sub-species, and in fact in new species as well. Each form is only slightly different from the one before it, therefore making a crisp boundary for "Asian" and "European" is as difficult as determining which organism was truly the first mammal; You can tell at either end of the spectrum that there are distinct enough differences for classification, but the middle of the spectrum is far messier. The issue is not that there are no races, species, etc, the issue rather is that you don't seem to grasp how classifications have to be applied in the real world.

I think part of the problem here is that there are two "ideas" floating around in this debate that are being conflated:

1) that races are distinct and coherent sub-species groups that can be easily recognized by eye

and

2) that there are biological underpinnings of observed differences between individuals that are often summarized by the term 'race'.

The former cannot really be true because, with minor exceptions of tribes in the remote amazon, all 'races' of people have had individuals that interbred with at least one member of some other 'race'. So there cannot be any long term coherence in such races. Furthermore, the within-race genetic variation is often comparable to between-race genetic variation.

But the latter (#2) is almost certainly true. There are alleles for variants of skin colour and facial features and other anatomical features that are probably very high frequency in certain groups that are often called 'races' and low in others that are said to not be part of those races. Because of this, there is goign to be some kind of rough correspondence b/w some races and easy-to-recognize features. The question is how far you want to push the definition of race here and how much real useful biological work is it doing for you.

By the way, the phylogenetic trees of mtDNA only characterize a very small portion of the history of humans...we have lots of genes that have different phylogenies because of recombination and syngamy.

InfuriatedSciTeacher:"To those who are arguing that there are no races because there are no distinct boundaries: That problem exists in the classification of sub-species, and in fact in new species as well."

But - this just shows you that species is just a useful concept not quite reflecting the biological reality (or reflecting it properly only outside hybrid zones and outside areas of speciation). Races, however, are not as useful as this. Populations with different characteristics of some trait/genotype, yes, but races, not quite.

"Populations with different characteristics of some trait/genotype, yes, but races, not quite."

So you've admitted that there is such a thing as race. Now please give us your definition of it.

I'm a blue-collar guy so I don't get into the heavy genetics of it, I go with how a sub-species is defined when I'm out there birding, herping, botanizing, or studying whatever else intrigues me in the natural world. And out there it's fairly straightforward - if there is a slight difference that gives you an advantage in certain geoclimatic conditions then you are a sub-species/race. Below that would be a morph, which is basically a regularly occurring difference which may or may not one day lead to the formation of a new race. An easily observable morph will be visible shortly as populations of Rough-legged Hawks, Buteo lagopus, move down into southern Ontario. Look for the dark morph, which is not melanistic, but rather has a much darker pattern over a wider area of its body.

If you want to be “scientific” and argue that “races” of humans exist, YOU have the burden of proof.Here is a brief list of some of the questions that you should be able to adequately answer before you can claim victory:

1.Genotype or Phenotype?How do you deal with the fact that genetics and appearance correlate less and less the more traits you include in your analysis?

2.Which traits makes a “race”?Are they the traits that a small part of the population have in common or are the traits that the most people have in common? What do you do when that leads to two different answers?

3.How many “races”?Four? Thirty? A thousand? Eight million? Six billion?

4.Lumping or Splitting?Where do you draw the line that will allow you to discreetly classify people as members of one “race” and not another?

5.What do you do if there are more total members of “mixed races” than total members of “pure races?”I could go on, but I think you get the point.

You can make that exact same argument about colours, or literary genres, or art styles, do you claim those groups don't exist either? Humans are very good at recognizing patterns (sometimes too good unfortunately, ie paradolia) and we suck at describing them, because we can't formalize a concept in precise terms doesn't mean the concept is invalid.

I suspect the only reason you're treating race as different is for political reasons. And there are valid political reasons for rejecting race as a concept. However, I don't think its valid to claim you're rejecting race on a scientific basis by applying a standard that you don't apply to any number of similar concepts that lack the political implications.

aluchko, I happen to be politically and philosophically hostile to the concept of “race.” It has inspired me to think about, and analysis the thoughts of others on, the subject. However, I can't imagine how this would make me less knowledgeable about the subject.

“Race” is a social construct. It is not a scientific fact.All of your counter examples are also social constructs (for example, “red” is a social construct), but they do have scientific equivalents (see wikipedia).It's not up to me to prove that there's nothing wrong with the idea of “race” any more than it's up to me to show how many angels can dance on the head of a needle. It's up to the proponents of the use of “race” to show that it is anything other than a scientifically useless idea (knowledge that an individual member possesses one trait gives you no additional knowledge about whether any other particular member possesses the same trait).

There is a perfectly good scientific concept that works much better than “race” ever could. Each hereditary unit consists of two types of relationships: 1. parents and their offspring, and 2. siblings. We call them “families”.

As Lewontin argued years ago, the concept of race is a social and not genetic entity. This is becuase there is more variation of genes within a "race" rather than between them. He provides examples of the polymorphisms in the ABO blood groups along with other genes. Drawing from 4 research papers, he shows that the variation within a race is 85% as opposed to less than 7% between races. You may search for his 1 hour lecture on YouTube or read his books on human genetic variation. It seems the evidence is pretty convincing.

As Lewontin argued years ago, the concept of race is a social and not genetic entity. This is because there is more variation of genes within a "race" rather than between them.

That's a completely ridiculous argument.

The same thing is true of newly formed species, which, of course, come from races as Darwin so clearly explained back in 1859.

Do you deny the existence of closely related species on the grounds that there's more variation within them than between them?

Perhaps you can enlighten us on your strange theory of speciation? How do you imagine that new species could form from a single species (by cladogenesis) without there ever being a time when there's more variation within the two separating populations than here is between them?

Lewontin's writing on this topic is very confusing. I suspect it's more motivated by his opposition to racism and biological determinism than by biology. However, he does not use the argument you use to refute the existence of races. He uses it to argue that even if races exist we are all still more similar genetically than we are different [see the aptly titled: Confusion About Human Races]

If you want to be “scientific” and argue that “races” of humans exist, YOU have the burden of proof.

I have already stated my thoughts on this matter, I will restate them for further clarification. If a species contains members with traits confined to specific environmental conditions, and if those traits confer advantages under those conditions (with the obvious assumption that those traits have been a constant over many generations), then those members would constitute a subspecies or race. Over time those differences may become so pronounced that the race would be classified as a separate species. Nobody could seriously state that the differences between Homo sapiens nominally classified as negroid or caucasoid (to pick but two) do not confer advantages to each, assuming that they are living under purely natural (non-technological) conditions, therefore they constitute races.

I will be the first to agree that from a sociological standpoint the term is very controversial, and with good reason (I lived through the 60s, and loudly cheered every hard-won victory for racial equality). But in the field of biology I see no need for it to be contentious outside of the actual determination of the difference itself - the fact that advantageous physical differences exist between humans in different areas of our world is incontrovertible.

Dr. moran it would be very beneficial if you analyzed the technical content of Dr. Lewontin's essay:[Confusion About Human Races] that you referenced above, as he concludes the essay with "Thus, there have been repeated attempts to reassert the objective biological reality of human racial categories despite the evidence to the contrary."

seeing that this position is contary to yours it would be interesting to see where the difference lies.

Dr. moran it would be very beneficial if you analyzed the technical content of Dr. Lewontin's essay:[Confusion About Human Races] that you referenced above,as he concludes the essay with "Thus, there have been repeated attempts to reassert the objective biological reality of human racial categories despite the evidence to the contrary."

Lewontin's points aren't much different from those you see here in the comments. His main goal in life is to combat biological determinism and this includes various forms of racism where people are assigned various characteristic based solely on their perceived race.

I strongly support him in these attempts. Lewontin is one of my personal heros.

However, there are times when he interprets biology in light of his social preferences and this is one of those times. Here's part of the final paragraph from the article.

In an attempt to hold on to the concept while make it objective and generalizable, Th. Dobzhansky, the leading biologist in the study of the genetics of natural populations, introduced the “geographical race,” which he defined as any population that differed genetically in any way from any other population of the species. But as genetics developed and it became possible to characterize the genetic differences between individuals and populations it became apparent, that every population of every species in fact differs genetically to some degree from every other population. Thus, every population is a separate “geographic race” and it was realized that nothing was added by the racial category. The consequence of this realization was the abandonment of “race” as a biological category during the last quarter of the twentieth century, an abandonment that spread into anthropology and human biology. However, that abandonment was never complete in the case of the human species. There has been a constant pressure from social and political practice and the coincidence of racial, cultural and social class divisions reinforcing the social reality of race, to maintain “race” as a human classification. If it were admitted that the category of “race” is a purely social construct, however, it would have a weakened legitimacy. Thus, there have been repeated attempts to reassert the objective biological reality of human racial categories despite the evidence to the contrary.

There are several issues here and, unfortunately, some of them are relevant and some aren't.

First, it's not correct to say that biologists have abandoned the concept of race in other species. Check out any evolutionary biology textbook or the scientific literature. You'll find lots of references to races or subspecies.

Second, Lewontin uses the common argument that there's no set of genetic markers that uniquely defines a particular race and there are many groups of people who don't fit conveniently into one of the classic races. Therefore races don't exist.

My argument—and I'm not alone in this—is that this is a strawman. No reasonable biologist would make the claim he attributes to them. Races are large clusters of individuals that are genetically isolated from each other. The frequency of alleles in those races are different. It is not a requirement that the races have been separated for such a long time that many alleles have become fixed.

No biologist would deny that there are hybrids in all species that have races. No biologist would deny that there are other, smaller, populations within the species that may not fit into the larger categories. Biology is messy. The same arguments could be applied to species but we all recognize the usefulness of the species concept.

Finally, Lewontin stoops to the lowest possible level of scientific debate when he implies that those of us who disagree with his biological arguments are doing so because we don't know the difference between race as a "social construct" and race as a biological concept.

I understand that for Lewontin the evils of the social construct outweigh any scientific value in identifying human races. That's where I differ. I think that scientific accuracy is paramount and, as a society, we just have to deal with the consequences.

Second, Lewontin uses the common argument that there's no set of genetic markers that uniquely defines a particular race...

I've actually had people tell me, with a straight face, that there is no genetic cause for skin colour. Well excuse me for only having a Grade 13 biology credit, but how the hell else can skin colour be determined if not by genes ? Is there a little gnome sitting in each delivery room with a set of paint pots? Maybe I'm missing something here, but is there any other way outside of short-term solar or chemical effects?

As Lewontin argued years ago, the concept of race is a social and not genetic entity. This is because there is more variation of genes within a "race" rather than between them.

That's a completely ridiculous argument.

The same thing is true of newly formed species, which, of course, come from races as Darwin so clearly explained back in 1859.

Do you deny the existence of closely related species on the grounds that there's more variation within them than between them?

Perhaps you can enlighten us on your strange theory of speciation? How do you imagine that new species could form from a single species (by cladogenesis) without there ever being a time when there's more variation within the two separating populations than here is between them?

Lewontin's writing on this topic is very confusing. I suspect it's more motivated by his opposition to racism and biological determinism than by biology. However, he does not use the argument you use to refute the existence of races. He uses it to argue that even if races exist we are all still more similar genetically than we are different [see the aptly titled: Confusion About Human Races]

The standard concept of defining species arises from their inability to produce viable offspring , not their genetic similarity. Thus, even if it was true that two species had greater genetic variability within rather than between them I would still classify them as separate species. The error in defining race is attempting to apply similar classification to humans which are but one species. That' s why the concept of race applies to genetic variability ,not the ability to produce viable offspring.

Moran said : << My argument—and I'm not alone in this—is that this is a strawman. No reasonable biologist would make the claim he attributes to them. Races are large clusters of individuals that are genetically isolated from each other. The frequency of alleles in those races are different. It is not a requirement that the races have been separated for such a long time that many alleles have become fixed.>>

>>>

Families are large clusters of individuals that are genetically isolated from each other. The frequency of alleles in those Families are different. It is not a requirement that the Families have been separated for such a long time that many alleles have become fixed

>> Nations are large clusters of individuals that are genetically isolated from each other. The frequency of alleles in those Nations are different. It is not a requirement that the Nations have been separated for such a long time that many alleles have become fixed

<< Any group of humans are large clusters of individuals that are genetically isolated from each other. The frequency of alleles in any group of humans are different. It is not a requirement that any group of humans have been separated for such a long time that many alleles have become fixed >>

<< Any group of humans in a pub or a plane are large clusters of individuals that are genetically isolated from each other. The frequency of alleles in any group of humans in a pub or a plan eare different. It is not a requirement that any group of humans in a pub or a plane have been separated for such a long time that many alleles have become fixed >>

Laurence A. Moran

Larry Moran is a Professor Emeritus in the Department of Biochemistry at the University of Toronto. You can contact him by looking up his email address on the University of Toronto website.

Sandwalk

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Quotations

The old argument of design in nature, as given by Paley, which formerly seemed to me to be so conclusive, fails, now that the law of natural selection has been discovered. We can no longer argue that, for instance, the beautiful hinge of a bivalve shell must have been made by an intelligent being, like the hinge of a door by man. There seems to be no more design in the variability of organic beings and in the action of natural selection, than in the course which the wind blows.Charles Darwin (c1880)Although I am fully convinced of the truth of the views given in this volume, I by no means expect to convince experienced naturalists whose minds are stocked with a multitude of facts all viewed, during a long course of years, from a point of view directly opposite to mine. It is so easy to hide our ignorance under such expressions as "plan of creation," "unity of design," etc., and to think that we give an explanation when we only restate a fact. Any one whose disposition leads him to attach more weight to unexplained difficulties than to the explanation of a certain number of facts will certainly reject the theory.

Charles Darwin (1859)Science reveals where religion conceals. Where religion purports to explain, it actually resorts to tautology. To assert that "God did it" is no more than an admission of ignorance dressed deceitfully as an explanation...

Quotations

The world is not inhabited exclusively by fools, and when a subject arouses intense interest, as this one has, something other than semantics is usually at stake.
Stephen Jay Gould (1982)
I have championed contingency, and will continue to do so, because its large realm and legitimate claims have been so poorly attended by evolutionary scientists who cannot discern the beat of this different drummer while their brains and ears remain tuned to only the sounds of general theory.
Stephen Jay Gould (2002) p.1339
The essence of Darwinism lies in its claim that natural selection creates the fit. Variation is ubiquitous and random in direction. It supplies raw material only. Natural selection directs the course of evolutionary change.
Stephen Jay Gould (1977)
Rudyard Kipling asked how the leopard got its spots, the rhino its wrinkled skin. He called his answers "just-so stories." When evolutionists try to explain form and behavior, they also tell just-so stories—and the agent is natural selection. Virtuosity in invention replaces testability as the criterion for acceptance.
Stephen Jay Gould (1980)
Since 'change of gene frequencies in populations' is the 'official' definition of evolution, randomness has transgressed Darwin's border and asserted itself as an agent of evolutionary change.
Stephen Jay Gould (1983) p.335
The first commandment for all versions of NOMA might be summarized by stating: "Thou shalt not mix the magisteria by claiming that God directly ordains important events in the history of nature by special interference knowable only through revelation and not accessible to science." In common parlance, we refer to such special interference as "miracle"—operationally defined as a unique and temporary suspension of natural law to reorder the facts of nature by divine fiat.
Stephen Jay Gould (1999) p.84

Quotations

My own view is that conclusions about the evolution of human behavior should be based on research at least as rigorous as that used in studying nonhuman animals. And if you read the animal behavior journals, you'll see that this requirement sets the bar pretty high, so that many assertions about evolutionary psychology sink without a trace.

Jerry Coyne
Why Evolution Is TrueI once made the remark that two things disappeared in 1990: one was communism, the other was biochemistry and that only one of them should be allowed to come back.

Sydney Brenner
TIBS Dec. 2000
It is naïve to think that if a species' environment changes the species must adapt or else become extinct.... Just as a changed environment need not set in motion selection for new adaptations, new adaptations may evolve in an unchanging environment if new mutations arise that are superior to any pre-existing variations

Douglas Futuyma
One of the most frightening things in the Western world, and in this country in particular, is the number of people who believe in things that are scientifically false. If someone tells me that the earth is less than 10,000 years old, in my opinion he should see a psychiatrist.

Francis Crick
There will be no difficulty in computers being adapted to biology. There will be luddites. But they will be buried.

Sydney Brenner
An atheist before Darwin could have said, following Hume: 'I have no explanation for complex biological design. All I know is that God isn't a good explanation, so we must wait and hope that somebody comes up with a better one.' I can't help feeling that such a position, though logically sound, would have left one feeling pretty unsatisfied, and that although atheism might have been logically tenable before Darwin, Darwin made it possible to be an intellectually fulfilled atheist

Richard Dawkins
Another curious aspect of the theory of evolution is that everybody thinks he understand it. I mean philosophers, social scientists, and so on. While in fact very few people understand it, actually as it stands, even as it stood when Darwin expressed it, and even less as we now may be able to understand it in biology.

Jacques Monod
The false view of evolution as a process of global optimizing has been applied literally by engineers who, taken in by a mistaken metaphor, have attempted to find globally optimal solutions to design problems by writing programs that model evolution by natural selection.